Impression tray



Feb. 23, 1943. c. P. JOCHUM IMPRESSION TRAY Filed. March 2, 1942 2Sheets-Sheet 1 INVENT OR. BY Kari PJoc/zwm I Y 4 M Feb. 23, 1943. c, PJOCHUM IMPRESS'ION TRAY Fil ed March 2, 1942 2 sheets-sheet 2 111AVII/IIIIIIIIIIIIIIIIIIIIIIll 1/14 'IIIIIIIIIllllllllllllllllfi BY Carl FJ Z2352,

Patented Feb. 23, 1943 IMPRESSION TRAY Carl P. Jochum, Blue Island,111., assignor of onehalf to Harry 0. Schuldt, Blue Island, 111.

Application March 2, 1942, Serial No. 432,943

3 Claims.

The present invention relates to dental impression trays and more inparticular to improvements in water jacketed trays of the typedesignated.

Among the objects of the present invention is to provide a novelimpression tray of multi-part co st t on adapting, it for use withvarious types of dental material.

More particularly the present invention includes as an object the ideaof forming the tray in such a way as tomprovide increased surface areasfor the mold cavity to secure more eflicient cooling effects from thecooling fluid used in conjunction therewith.

Another object of the present invention is to provide a novel dentalimpression tray of multipart construction, the parts being releasablysecured to one another whereby one of the parts may be used for takingimpressions with dental plaster, andthe combined assembly may be usedfor taking impressions with hydrocolloid elastic material.

A still further object of the present invention is to provide animpression tray having a part which is adapted to receive the impressionmaterial releasably secured to other parts of the tray, whereby the saidremovable part may be readily and easily disconnected for sending to alaboratory or the like, while the remaining part or parts may be usedfor taking additional impressions either alone or in conjunction withanother removable part secured thereto.

Another object within the purview of the present invention is to providea water jacketed dental impression tray having its mold cavity formed bya tray member rigidly secured in position but provided with a pluralityof openings or perforations to increase the surface area for the moldcavity to thus provide increased cooling efiect upon the impressionmaterial.

The present invention further includes as an object the idea ofproviding a water jacketed dental impression tray in which one of thewalls forming the jacket and providing the core cavity, is perforated tocommunicate with the fluid passage therethrough whereby cooling mediummay come into immediate contact with the impression material to increasethe setting and hardening of the said impression material.

Other objects, features, capabilities and advantages are comprehended bythe invention, as will later appear and as are inherently possessedthereby.

Referring to the drawings- 1 Figure 1 is a topplan view of a bottomdental impression tray embodying the improvements according to thepresent invention;

Figure 2 is a top plan view of one of the elements of the tray assemblyshown in Figure 1 of the drawings;

Figure 3 is a view partly in section and partly in elevation, taken inthe plane represented by line 33 of Figure 1 of the drawings;

Figure 4 is a fragmentary view, partly in section and partly inelevation, taken in the plane represented by line 4-4 of Figure 1 of thedrawings;

Figure 5 is a fragmentary view, partly in section and partly inelevation, of a modified form of construction for a dental impressiontray embodying in substance the improvements shown in Figures 1 to 4 ofthe drawings;

Figure 6 is a top plan view of an upper dental impression tray embodyingthe improvements shown in Figures 1 to 4 of the drawings;

Figure 7 is a top plan View of another dental impression tray embodyinga modified form of assembly, varying somewhat from that shown in thepreviously illustrated embodiments;

igure 8 is a view partly in section and partly in elevation taken in theplane represented by line 88 of Figure 7 of the drawings; and

Figure 9 is a view partly in section and partly in elevation of stillanother modified form of impression trays embodying improvementsaccord,- ing to the present invention.

Referring now more in detail to the drawings, an embodiment selected toillustrate the invention is shown in Figures 1 to 4 of the drawings ascomprising a lower dental impression tray formed with inner and outerwalls 2 and 4, formed to provide a substantially U-shaped mold cavity,having the base 6 and the sides 8 and H], the walls forming the samebeing interconnected to provide a fluid passage [2 therebetween, whichfluid passage extends throughout the base 6 and side walls 3 and I0 toreceive a cooling medium such as water or the like, for a purpose to behereinafter more fully set forth, Disposed within the base 6 and betweenthe inner and outer walls 2 and 4 is a radially disposed partition 14terminating at one edge in the side wall 8 and merging at its other edgewith the wing partition elements It and I 8, likewise disposed betweenthe walls 2 and 4 but terminating short of the ends of the said walls toform a circuitous flow passage from one side of the partition member Itaround one of the wing partition members, thence around the other wingpartition member and 2 back into the environment of the said partitionl4 on its other side.

Connected to the water jacketed tray member above described are spacednozzles or conduits 20 and 22 radially disposed with respect to thewater jacketed tray, and being interconnected by the reinforcing web 24.One of the said conduits or nozzles communicates with the inner fluidpassage l2 on one side of the partition l4 and the other nozzle orconduit communicates with the fluid passage l2 on the other side of thepartition I4. It will be apparent, therefore, that the nozzles 20 and 22serve in the capacity of inlets or outlets for the said fluid passage I2so that water or other cooling medium may be introduced into either oneof the nozzles and into the fluid passage I2, and after circulatingabout the partition means as disclosed will flow out through the otherof the said nozzles. The provision of such a fluid passage within thetray member, as described, permits the cooling of impression materialwhich may be used in the tray for taking dental impressions. Thestructure as above described is particularly adapted for taking dentalimpressions from dental plaster which is readily cooled through themedium of water or the like circulated through the fluid passagehereinbefore described.

The embodiment shown in Figures 1 to l, however, not only serves as animpression tray for receiving and taking impressions in dental plaster,but likewise includes additional structure in the assembly which adaptsit particularly for use in connection with hydrocolloid elasticmaterial. In order to adapt the tray structure for use of the lattermaterial, the assembly further includes a tray member 26 conforming inshape to the mold cavity formed by the inner wall 2 of the previouslydescribed tray member, but being formed with a plurality of openings orperforations 28 which, when the tray member 26 is inserted in positionwithin the said mold cavity, are in communication with the surface areasof the inner wall 2. In order to adapt the present embodiment for use inconnection with either dental plaster or hydrocolloid elastic material,the said tray member 26 is removably secured to the first described traymember through the medium of clips or brackets 30 and 32 disposed at theends of the tray assembly and a resilient clip element 34 disposed atthe top of the side wall 8 in opposed relation to the clips 3!] and 32.It is quite apparent that the tray member 26 is removably secured inposition by the overhanging relation of the clips 30 and 32 in respectthereto at its ends, and by the resilient clip element 34 which isadapted to receive the opposite marginal edge of the tray member 26 whenthe same is pressed down into intimate association with the mold cavityof the first described tray member.

Removal of the tray is readily accomplished by releasing the resilientclip member 34 from its engaging relation with the tray member 26whereby the said tray member, with the impression material therein, maybe removed after the impression has been taken. This ready releasableremovability of the tray member 26 in respect to the water jacketed trayserves to permit the single water jacketed tray to be used with anynumber of the perforated tray members, thus decreasing the cost ofequipment necessary to take dental impressions and permitting the use ofthe water jacketed tray at times when one or more of the perforatedtrays may have been sent to the laboratory.

The embodiment shown in Figures 1 to 4 has the further attribute ofgreatly increasing the effectiveness of the cooling agent or mediumbeing circulated in the fluid passage [2, in that the perforations inthe tray member 26. greatly increase the effective area of thehydrocolloid elastic material being cooled by the cooling medium.

The embodiment shown in Figures 1 to 4 has an additional feature ofconstruction covering a screw element 36 for positively holding the traymember 26 in position within the mold cavity of the outer water jacketedtray. Other than providing for the additional screw element 36, theembodiment shown in Figure 5 conforms in all respects to that shown inFigures 1 to 4 of the drawings.

In Figures 1 to 4 improvements in accordance with the present inventionhave been shown as being incorporated in a lower dental impression tray,but the invention is not limited to such structure and may beincorporated in upper dental impression trays such as disclosed inFigure 6 of the drawings. In this embodiment the tray elements conformsubstantially to those shown in Figures 1 to 4, except that both thewater jacketed tray member as well as the perforated tray member areeach provided with a palate piece 38 bridging the immediately adjacentparts of the tray members conforming to those shown in Figures 1 to 4 ofthe drawings.

In addition to the novel characteristics of the invention as shown inFigures 1 to 4 of the drawings, the present invention contemplatesimpression tray structure conforming to that shown in Figures "I and 8illustrative of a modified form of assembly in which the outer traymember 40 conforms substantially to that shown in Figures 1 to 4. Theouter tray member 40 is provided with a flow passage for circulation ofa cooling medium therethrough, and is formed with a mold cavity adaptedto receive a second tray member 42 perforated at a plurality of pointsas at 44. In this modification, however, the tray member 42 ispermanently ailixed to the tray member 46 as by welding along themarginal edges 46 or at any other place desired, to provide a rigidstructure particularly adapted for taking impressions in hydrocolloidelastic material. This tray with its recessed mold cavity provides avery efficient impression tray in that the effective cooling areathereof is greatly increased over that which would be secured merely bythe inner wall of the tray member 40. It is, of course, understood thatthe welding of the tray member 42 to the tray member 40 is of such acharacter that the same may be easily broken any time it is desired toreplace the tray member 42 should the same need replacement because ofwear or damage. The weld material along the marginal edges of the twotray members is such as to provide a smooth surface, free fromprojections or other undesirable marginal characteristics.

The present invention further contemplates a modified form ofconstruction for dental impression trays particularly adapted for use inconnection with the taking of impressions in hydrocolloid elasticmaterial, the same being shown in Figure 9 and conforming in itsstructure substantially to the water jacketed tray member shown inFigures 1 to 4, except that in this embodiment the inner wall 48 isnotimperforate as is the wall 2 of the previously mentioned embodiment, but

is formed with a plurality of openings 511 permitting a certain amountof the hydrocolloid elastic material to enter into the fluid passage l2provided in the tray. This direct contact between the cooling mediumbeing circulated in the tray member and the hydrocolloid elasticmaterial leads to certain improved results from the standpoint of quicksetting of the material, and therefore has its advantages from thatstandpoint, although the said device is subject to a certain amount ofcriticism on the score that such material enters the fluid passage l2and accordingly the device must be cleaned more frequently than isnecessary in the previously described embodiments of the invention.However, under certain circumstances the increased cooling effect uponthe hydrocolloid elastic material secured by using this type of traymore than offsets the disadvantages from clogging, and this device has agreat deal of utility in the art.

In all of the embodiments of the invention hereinbefore described, it isnoted that the base as well as the sides of the outer tray member arehollow, so as to provide a fluid passage l 2 through the device.however, is such as to contemplate the use of the various novel featuresof construction in connection with an outer tray of any desiredconstruction and one in which the fluid passage or pas- The invention asherein described, 2

sages therethrough may vary from those as here- 30 in disclosed, withoutdeparting from the spirit of the invention.

While I have herein described and upon the drawings shown illustrativeembodiments of the invention, it is to be understood that the inventionis not limited thereto but may comprehend other constructions,arrangements of parts, details and features Without departing from thespirit of the invention.

What is claimed is:

1. An impression tray comprising a, tray member providing a mold cavityand having spaced base plates and upstanding walls, partitions providingan internal circuitous fluid passage within said tray structure, inletand outlet means for said fluid passage, and a perforated tray memberdisposed in said mold cavity in association with said first named traymember.

2. An impression tray comprising a tray member providing a mold cavityand having spaced base plates and upstanding walls, partitions providingan internal circuitous fluid passage within said tray structure, inletand outlet means for said fluid passage, a perforated tray memberdisposed in said mold cavity in association with said first named traymember, and means removably securing said second named tray member inassociation with said first named tray member.

3. An impression tray comprising a tray member providing a mold cavityand havin spaced base plates and upstanding walls, partitions providingan internal circuitous fluid passage within said tray structure, inletand outlet means for said fluid passage, a perforated tray memberdisposed in said mold cavity in association with said first named traymember, and means fixedly securing said second named tray member inassociation with said first named tray member.

CARL P. J OCHUM.

